Bracuiopopa. | UPPER PAL/EOZOIC MOLLUSCA. 478 
M. de Koninck’s figures under the aboye name papillatus are very good, and will enable people to recognize 
this species more easily than when only that of Mr Phillips was accessible. He has, however, in his fine 
monograph on the genus Productus, figured and described an entirely different species under the name Pro- 
ductus spinulosus, viz. the species named P. Koninckianus by M. de Verneuil, and which is far more gibbous, 
and marked with distinct longitudinal sulci; and he makes the remark that “il est assez probable que 
M. M°Coy, dont la déscription ne fait pas mention de cdtes longitudinales, a aussi confondu ce Productus avec 
une espece voisine,” as well as MM. de Buch and Phillips, who also considered the P. spinulosus of Sowerby to 
be without longitudinal ridging. I believe that in my volume on the mountain-limestone fossils of Ireland, to 
which M. de Koninck alludes, I have accurately identified the true P. spinulosa of Sowerby; but in that work I 
also retained the name Producta granulosa of Phillips for those specimens resembling P. spinulosa, but having 
the granules extremely crowded and obtuse. The great number of Scotch specimens which I have recently 
examined prove to a certainty that these are merely varieties of one species ; and the only question remained as 
to whether M. de Koninck or myself were correct in our notions of the true Producta spinulosa; and to set this 
question at rest I wrote to Mr Sowerby, who had the kindness immediately to reply, that he rather agreed with 
me that there was no longitudinal suleation in the species; but that as the original type specimen was in the 
collection of the Rey. Dr. Fleming, he could not be sufficiently certain to decide the point. On this I wrote to 
Prof. Fleming as to the characters of the original type specimen, and enclosing in the letter a small specimen, 
intermediate between the variety P. granulosa of Phillips, and what I considered the true type of P. spinulosa 
(Sow.), requesting his decision as to whether it was, or not, the latter species. I have just received a most full 
and satisfactory reply, in which Dr. Fleming says: “‘ My most perfect specimen of Productus spinulosus, and 
the one figured by Sowerby, is nor sulcated longitudinally ;” the underlining of the latter words being his own; 
and further on he adds: ‘“‘ The shell now returned is certainly a young P. spinulosus.” The specimen so 
authenticated from the Beith limestone is especially marked in the University collection for the examination 
of those interested in the discussion. 
Position and Locality —Common in the carboniferous limestone of Derbyshire; carboniferous limestone of 
Beith, Ayrshire. 
Propucta striata (Fischer Sp.). 
Ref. and Syn. = Mytilus striatus Fisch. Oryct. Moscow, t. 19. f. 4.= Pinna inflata Phill. Geol. York. t. 6. f. 1. 
= Lima Valdaica and Productus limiformis V. Buch. Ueber. Productus, t. 1. f. 4 to 6.= Lepteena anomala 
Sow. Min. Con. t. 615. figs. La, c, d (not 6) =Productus striatus de Kon. Monog. Prod. t. 1. f. 1. 
Desc.—Form very irregular, usually triangular, greatly elongated, nearly in one plane, increasing very irre- 
gularly towards the front margin; some specimens being broad, ovate, and others very narrow, trigonal, and 
sometimes slightly arched to one side or the other; beak pointed; the side and front margins in general rather 
abruptly, but very irregularly, sloped and waved without symmetry, the surface being in consequence marked with 
short, very irregular, interrupted indentations of growth, marking the former irregularities of the margin: hinge- 
line generally almost obsolete, so that the posterior end is gradually pointed ; in some rare, short, wide specimens 
it is dilated into obscurely defined, obtuse-angled ears, bearing one or two rows of slender bristle-like spines, two 
or three lines long; shell extremely thin. Entering valve almost in contact with the receiving one, and resem- 
bling it in all respects; striz harsh, rugged, rounded, or slightly flattened, coarse, irregularly waving, and in- 
creasing very frequently in number by interpolation of new striz, nearly equalling the others in size (about seven 
strize in two lines, at one inch from the beak, sometimes rather finer towards the margin, but nearly equal on all 
parts of the shell) ; intervening sulci very deep, but much narrower than the strize; no spine-bases on the body 
of the shell. Muscular impressions very faintly marked on the casts. 
This shell is so extremely variable in form that it is useless to attempt to give any proportional measure- 
ments; perhaps the most common sizes are three or four inches long and two inches wide at the front, and the 
beak and front margin and all the intervening part of the shell being approximately in one plane; and of this 
type, which generally forms closely packed masses, I have seen Irish specimens one foot long and five inches 
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